1. Field of the Invention
The present invention generally relates to a method of caustic alkali treatment of a knitted work.
2. Description of the Prior Art
Two conventional methods of caustic alkali treatment for knitted work are known, namely, (1) to treat the knitted work as is in the shape of a tube and (2) to treat the knitted work after cutting open the same into the form of a cloth from the shape of a tube.
The demerits in the case where the knitted work is subjected to the caustic alkali treatment are as follows. Specifically, since the knitted work shrinks in the widthwise direction and at the same time, extends in the lengthwise direction during the process of the scouring (or degumming) and the bleaching treatment, the knitted work remains shrunken in the widthwise direction and extended in the lengthwise direction after the completion of the caustic alkali treatment, resulting in a disadvantage such that a product made of the knitted work considerably unfavorably shrinks in the wash. Moreover, the caustic alkali treatment is conducted in the manner that the opposite left and right ends of the tubular knitted work are held down, and therefore, when one of the opposite left and right ends is cut open to be unfolded after the treatment, the knitted work thus unfolded is stained with a striped mark, that is, a so-called "center mark" in the center thereof.
On the other hand, the demerits in the case where the knitted work is subjected to the caustic alkali treatment after it is cut open into the form of a cloth are as follows. That is, the knitted work which shrinks in the widthwise direction and extends in the lengthwise direction due to the scouring (or degumming) and the bleaching treatment remains as is, even through the caustic alkali treatment, and accordingly, it is disadvantageous that the knitted work is apt to be short of width, or the product made of the knitted work undesirably shrinks in the wash.
Meanwhile, in order to eliminate the disadvantages or demerits found in the case where the knitted work is subjected to the caustic alkali treatment in the form of an unfolded cloth, there is a way to bring the knitted work first into the caustic alkali treatment without the scouring (or degumming) and bleaching treatment done, and then into the scouring (or degumming) and the bleaching treatment. In accordance with this manner of caustic alkali treatment before the scouring (or degumming) and the bleaching treatment, although the product does not shrink in the wash, it lacks good luster, nor does the caustic alkali treatment have a good effect.
As is explained above, it has been impossible to produce a satisfactory product in accordance with the prior art caustic alkali treatment. Particularly, in consequence of the spread of washing machines equipped with driers of tumble-dry system in recent years, such an improvement is strongly desired for a process which can prevent the product of the knitted work treated in accordance with the above-described (1) or (2) method from shrinking even after the product is washed and dried by a washing machine with a tumble-dry drier.